Aircraft: B757
Phase of flight: Parked; Cruise; Taxi
Anomaly: Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

I would like to begin by praising my crew who performed flawlessly; efficiently and safely throughout the events of the day. My First Officer was awesome; as he flew the airplane and kept ATC advised with updates as we progressed through the event; and asserted his thoughts on where we should go and do; as I worked the problem with Maintenance and Dispatch. ALL of my flight attendants communicated clearly and gave updates as our event progressed. My crew members should all be recognized for their excellent work today! During cruise at FL350; the center autopilot malfunctioned. Annunciations were: Red Autopilot Disconnect Annunciator; Amber Autopilot Annunciator; Master Warning/Caution Lights and sirens. I held the yoke and to my surprise; the autopilot was still engaged with all of the warnings; so I used the thumb switch to disconnect the autopilot and selected the Left/Right Autopilots to check their operations. They both worked fine; so I tried to re-engage the center Autopilot and it failed immediately; just as initially. I selected the right autopilot for the remainder of the flight. I used ACARS to have a phone patch to Maintenance. I briefed both Maintenance and Dispatch. During this briefing the purser called up and told me that there were fumes throughout the cabin. My First Officer told me so I relayed this to Maintenance and Dispatch. I told Dispatch/Maintenance to standby. My First Officer got out the QRH and began running the list with me. We turned off the Utility Busses and recirculating fans which allowed greater airflow which caused the fumes to dissipate. The flight attendants had preemptively turned off the In Flight Entertainment (IFE); lighting; and oven switches to reduce electrical loads and to stop the sources of fumes. This was excellent work by my flight attendants as this showed initiative/understanding of how serious the situation was and what actions to perform without being told to do so. I finally got back to Maintenance/ Dispatch; and relayed the above. I asked for WX for several enroute airports. After conferring with my First Officer; we decided that short of smoke or fire; that we would divert to a major Maintenance station; otherwise we would divert to a nearby smaller airport. I advised Dispatch of this and she concurred. We terminated the patch and then my First Officer pulled out the diversion checklist. We increased Mach to M.83; I had my First Officer declare the emergency; turned directly for the divert airport and set up for the approach. We made a normal landing. The trucks were waiting for us. As we turned off of the runway we received another EICAS message; EQPT OVHT and the fumes returned and were increasing. My First Officer spoke with Ramp as I spoke with Ground and Operations. OPS asked me: 'Do you want us to image the airplane?' I did not know what this meant; so I told him no and that we wanted to get to the gate ASAP; because we were going to loose instrumentation and communications very quickly. Both my First Officer and I relayed to Ramp and Ground that if we do not respond that we would be heading directly to the gate. We arrived at the gate and everyone was waiting for us. CFR Personnel came inboard and scanned the airplane for hot spots; and found none. CFR left the airplane. I debriefed CS/Inflight and Flight Ops personnel. CS deplaned the passengers and sent them to our new gate or rerouted the passengers. Maintenance was debriefed my First Officer and me. I filled out the Fire; Smoke; and Fumes form and gave it to Maintenance. The Assistant Chief Pilot asked us if we were OK to continue. We both wanted to continue to our next station; but expressed how tired we were going to be if we had to continue on the third leg later; so he had Scheduling re-crew the last leg. My First Officer also picked us up some food as we had not eaten on the diversionary leg. We were both thankful for his kindness. An available First Officer was able to secure our outbound flight papers with great difficulty; since we were so far from flight ops. On the day after; I called Tower and spoke with the Chief and another Controller and explained what happened; and asked what his statement meant? He told me that it was OPS who asked me the question about the 'Imaging.' I explained that we have never heard of this and that for future reference; that they should use phrases with an explanation because; I WOULD HAVE LIKED TO HAVE KNOWN WHAT HE WAS TALKING ABOUT!!! They understood and told me that memos would be forwarded to appropriate people. I also called the Firehouse and spoke with CHIEF. I explained everything to him as well and he understood the terminology issue and said that he would also forward this to appropriate people because; COMMUNICATIONS ARE THAT IMPORTANT! I called Dispatch/ Maintenance and was briefed that the right Re-circulation fan had seized and was the culprit in our problem. What made this problem difficult was the timing of both failures and being to separate the problems which we were not able to do! This would make a great loft! During recurrent training it would be nice if the Training Center would 'educate' both Pilots and Flight Attendants about these 'Secret Words from CFR' and perhaps have a chat with CFR to find out any other phrases that might be useful to us if we might be.....ON FIRE! OTHER ISSUES: The QRH remains a problem for locating and using checklists. It would be nice if the party responsible for the verbiage on the QRH to annotate the EICAS MESSAGE FIRST; THEN THE DESCRIPTION OF THE ISSUE!!! During recurrent training we must be made aware of new and useful verbiage/information from other agencies like CFR/Tower/Operations. I would have used these services had we understood their communications! My worst fear is having a scenario like this at night over water near the mid flight point! It would be great to reiterate how important it is to turn directly for your alternate and increase speed to get to a runway! Lastly; it would be so nice if we could access the Flight Plans more easily! I understand the; 'Fit For Life Program' at work; but it really bugs me that I have to run to Flight Operations to pull up the papers for the next leg. If you don't believe me then speak with the First Officer who retrieved our flight plan. I do not want to cause a delay due to the flight plan system; so please help all of us out here! A B757 Center Autopilot malfunctioned at cruise when it indicated disconnected while still engaged. Then the flight attendants called with smoke and fumes in the cabin. An emergency was declared and the flight diverted where Maintenance discovered a failed recirculation fan.